Benign prostatic hypertrophy or hyperplasia (BPH) is one of the most common medical problems experienced by men over 50 years old. Urinary tract obstruction due to prostatic hyperplasia has been recognized since the earliest days of medicine. Hyperplastic enlargement of the prostate gland often leads to compression of the urethra, resulting in obstruction of the urinary tract and the subsequent development of symptoms including frequent urination, urgency, decrease in urinary flow, nocturia, pain, discomfort, and dribbling.
One surgical procedure for treating BPH is transurethral needle ablation (TUNA). The TUNA technique involves transurethral delivery of an electrically conductive needle to the prostate site. The needle penetrates the prostate in a direction generally perpendicular to the urethral wall, and delivers electrical current to ablate prostate tissue. The electrical current heats tissue surrounding the needle tip to destroy prostate cells, and thereby create a lesion within the prostate gland. The destroyed cells may be absorbed by the body, infiltrated with scar tissue or become non-functional.
U.S. Pat. No. 5,807,309 to Lundquist et al. discloses an example of a transurethral ablation device that includes a disposable needle assembly. U.S. Pat. No. 5,964,756 to McGaffigan et al. describes another transurethral ablation needle device having a reusable handle and a replaceable cartridge assembly. Table 1 below lists documents that disclose devices for transurethral ablation of prostate tissue.
TABLE 1Patent NumberInventorsTitle5,807,309Lundquist et al.Transurethral Needle Ablation Deviceand Method for the Treatment of theProstate5,964,756McGaffigan et al.Transurethral Needle Ablation Devicewith Replaceable Stylet Cartridge
All documents listed in Table 1 above are hereby incorporated by reference herein in their respective entireties. As those of ordinary skill in the art will appreciate readily upon reading the Summary of the Invention, Detailed Description of the Preferred Embodiments and Claims set forth below, many of the devices and methods disclosed in the patents of Table 1 may be modified advantageously by using the techniques of the present invention.